Let me try to enlighten you.
You posted a measurement of 0.223. That’s not a .223 Remington which is the proper name for the cartridge. In order to use the name of the cartridge, you would drop the zero and simply write .223 and even drop the Remington name.
If you wanted to use the measurement for that particular caliber, you would have to write 0.224.
Also, I haven’t quite understood why Freepers insist on writing .45 Long Colt. The “Long” doesn’t give it any more boost to the proper name of .45 Colt.
Because there are TWO Colt rounds in .45 caliber. The .45 ACP (Automatic Colt Pistol) and the .45 Long Colt that is typically used in revolvers.
While correct, the use of "long" helps further distinguish it from .45 Automatic Colt Pistol.
The only acceptable name for a cartridge is that adopted by SAAMI and ANSI. Street slang for cartridge names only adds confusion to an already somewhat disorganized system. Some incorporate the bullet diameter, others the firearm bore or groove diameter and some neither.
<>P> The .38 Special is one of the latter.
It certainly isn't correct to call a .30-06 Springfield a ".308" because of its bullet diameter. It is also not correct to call a .223 Remington a .223 because that is not its correct name, or bullet diameter or bore diameter or groove diameter and it certainly is not a .223 Winchester Super Short Magnum. Any time that layman gun nuts try to improve cartridge names (or just don't know better) the shooting sports suffer. What kind of fool doesn't know that there never has been and never will be a cartridge designation of "45 Long Colt"? That same crowd isn't aware that the ACP designations were obsoleted before WWII. Some folks never seem to get the message. Look at the headstamp, Stupid!
One day soon that crowd will attempt to rename the ".45 GAP" as the ".45 Short Auto" and the ".45 Win Mag" as the ".45 Long Auto". Maybe they can rename the ".454 Casull as the ".45 Extra Long Colt". Etceteras. There is no end to their creativity.